Hodgkin Lymphoma Staging and Management

Introduction to Staging

• The Ann Arbor classification system with Cotswolds modifications is used for staging Hodgkin lymphoma, dividing the disease into four stages (I-IV) based on anatomic distribution of lymph node involvement relative to the diaphragm, with PET-CT as the preferred imaging modality for staging FDG-avid disease 1, 2.

Core Staging System

• The staging framework defines four anatomic stages: Stage I (single lymph node region or one extralymphatic site), Stage II (two or more lymph node regions on the same side of the diaphragm), Stage III (lymph node regions on both sides of the diaphragm), and Stage IV (diffuse involvement of one or more extralymphatic organs or sites) 3, 4.

Symptom Classification

• Each stage is subdivided based on systemic symptoms, with "A" designation indicating no systemic symptoms and "B" designation indicating presence of at least one symptom such as unexplained weight loss, recurrent fever, or night sweats 3, 4, 5, 6, 7.

Bulky Disease Definition

• Bulky disease is defined by a mediastinal mass ratio (MMR) >0.33 or a mediastinal thoracic ratio (MTR) >0.35, and is a critical modifier with prognostic implications 3, 5, 7.

Modern Imaging-Based Staging

• PET-CT is the standard staging modality for FDG-avid Hodgkin lymphoma, replacing older invasive procedures, and is preferred over CT alone 1, 2, 7.

Required Staging Investigations

• Required staging investigations include PET-CT scan, contrast-enhanced CT, complete blood count, erythrocyte sedimentation rate (ESR), and comprehensive metabolic panel 7, 8.

Clinical Risk Stratification

• Patients are classified into three prognostic groups: early-stage favorable, early-stage unfavorable, and advanced-stage disease, which guide treatment intensity 5, 6, 7.
• The International Prognostic Score (IPS) identifies seven adverse factors for advanced disease, including age ≥45 years, male gender, stage IV disease, low albumin, low hemoglobin, high white blood cell count, and low lymphocyte count 5, 6.

Key Staging Principles

• The National Comprehensive Cancer Network (NCCN) recommends that A/B suffixes should only be included for Hodgkin lymphoma, not for non-Hodgkin lymphoma, as stated in the Lugano classification (2014) 1, 2.
• The American College of Radiology and other guideline societies support the use of PET-CT for staging Hodgkin lymphoma, given its high sensitivity and specificity 1, 2, 7.